This invention relates generally to methods and apparatus for dispensing fine powder. More particularly, this invention relates to methods and apparatus for the controlled dispensing of a plurality of equal quantities of powder into an equal number of containers. The invention is particularly directed to a mass production technique wherein fine powder reagents may be controlled and handled precisely in a production line for dispensing equal amounts simultaneously of a fine powder reagent into a plurality of waiting containers in the line.
In the handling of powder reagents, one of the difficulties in handling the powder is controlling it so that micro quantities may be dispensed in the powder amount into containers. When several containers are to be filled simultaneously, the control aspect of the situation becomes much more difficult. As will be understood by practitioners-in-the-art, when the powder involved is a reagent for use in medical applications, for example, it is much more necessary that a precise micro quantity of the reagent powder be properly dispensed into each container. The powders are reagents contained in such tubes react subsequently with the addition of blood samples taken from patients in order to provide tests of various physical conditions involved with the patients. It will be understood that if there is any significant variation in the quantities introduced into each container, then the subsequent testing procedures may be affected. Another major problem involved, other than variations in the quantities of the powder being dispensed, of course, is the fact that the powder is easily disturbed in its conveyance from one place to another so that the micro quantities involved with each dispensing procedure are affected.
With this invention, by contrast, methods and apparatus are provided for the precise controlled dispensing of fine powders. More particularly, the process and apparatus herein controls and dispenses simultaneously a plurality of quantities of such fine powders into a plurality of containers in the precise amounts required so that subsequent testing procedures utilizing the powder reagents will not be affected by any variation in the quantities dispensed.
The invention utilizes a plate having a plurality of bores or openings therein for receiving the individual quantities of powder being dispensed. The bores are configured and dimensioned to provide, in cooperation with the sweeping action of a brush across the plate, accurate micro-sized quantities of powder dispensed substantially simultaneously through each of the individual bores into containers positioned below the bores. The arrangement includes a conveyor system for conveying in a step wise manner a plurality of individual containers in a sequential arrangement so that groups of containers are continuously and sequentially positioned for receiving individual quantities of dispensed powder underneath the plate in a fully mechanized automatic production line.
Included herewith is an arrangement for depositing a plug of powder of precise quantity onto the plate prior to the dispensing thereof into the individual openings or bores in the plate. All of the power drives are arranged to operate sequentially in relation to each other in order to provide the proper interaction of parts therein. The arrangement is such that a push pull mechanism is utilized for the operation of the brush mechanism moving across the plate, as well as the dispensing of the plug of powder onto the plate. It should be understood that other similar devices such as a squeegee, for example, might be used to sweep across the surface of the plate. An elevator mechanism is utilized in conjunction with the movement of the push pull mechanism for moving the plate to position it for receiving, in a sequential manner, plugs of powder for the subsequent dispensing thereof into the bores on the plate. As will be appreciated by practitioners-in-the-art, the drive arrangements for the elevator mechanism and the push rod type mechanism for activating the brush may be under the action of compressed air, hydraulic pressure, or electric motors. At any rate, each of the drive mechanisms, including the step wide conveyor belt for conveying the groups of containers under the dispensing plate are under the action of a control mechanism, as will be appreciated, so that each individual part is activated or moved in relation to every other part in the desired sequence of operation.